Who is Participating?

The universal receivers logitech uses, allow you to pair a specific mouse or keyboard to the receiver, so only that mouse or keyboard will be able to talk to that receiver. On the other PC you would use another receiver and pair that one to another mouse. That makes sure they don't interfere with each other.

The same applies to bluetooth mice. They also have to be paired with the bluetooth radio in your PC, so only the paired device will talk to it. But Bluetooth is a little more difficult, as when you have Bluetooth discovery on on your PC, and a new device comes into range, it will ask you whehter you want to attach to it. So the universal receiver is the better option.

Use logitech mice that use the universal dongle. Those you can pair to a specific dongle so that only the dongle it is paired with will react. Or use a bluetooth mouse. Also those get paired to specific PC's.

If I understand correctly what a universal stands for is to use multiple devices with one receiver. I my case I want them function separate each mouse to the DVR its receiver is connected connected to. But the issue, thy interfere each other.